Data Caching for Enhancing Anonymity

Abstract

Abstract-The benefits of caching for reducing access time to frequently needed data, in order to improve system performance, are already well-known. In this paper, a proposal for employing data caching for increasing the level of anonymity provided by an anonymity system is presented. This technique is especially effective for user sessions containing bidirectional communication, such as anonymous web browsing. A framework is first constructed for capturing the effect of attacks on anonymity systems that have the ability to serve some incoming user requests from their cache. A system-wide metric is then presented for measuring the anonymity provided by such systems. It is shown that the anonymity level of such systems rises with the amount of data caching performed by them. This behavior is illustrated in an example threshold mix network.

An Accurate System-Wide Anonymity Metric for Probabilistic Attacks

“…The equivalence relation on perfect matchings, induced by such multiplicity, causes a reduction in anonymity. Bagai and Tang [14] analyzed the effect of employing data caching within the mix network. Their modified metric captures an increase in anonymity due to such caching.…”